1. Technical Field
The disclosure relates to molds, and particularly to a molding machine for forming an optical film.
2. Description of the Related Art
A liquid crystal display usually includes a backlight module and an LCD panel located in front of the backlight module.
The backlight module is a light source for the LCD panel. The backlight module usually includes a light element, a light guide plate, and several optical films, such as prism sheets and diffusion films. Most optical films include a polyethylene terephthalate (PET) substrate and an ultraviolet (UV) curable resin layer having microstructures on surface thereof to achieve specific features of the optical film, such as light focus or light diffusion. A method of manufacturing the optical film generally includes steps of: coating the PET substrate with UV-curable layer, forming microstructures on the UV-curable layer by roller imprinting, and an UV irradiation to cure the UV-curable layer.
However, light transmittance of the PET substrate is merely 90%, so 10% of light is lost before entering the UV-curable layer in operation. In addition, since the PET substrate and the UV-curable layer are formed by deferent machines and usually by deferent manufacturers, the cost of the PET substrates is considerable in the cost of the optical films. Moreover, since the PET substrate should be prepared before the coating process of the UV-curable layer, the delivery time of the optical films is apparently affected by the preparing of the PET substrates. The supplies of the PET substrates are running short, the delivery time of the optical films is delayed.
Therefore, it is desirable to provide a molding machine for forming an optical film, which can overcome the described limitations.